Restoring ocean fisheries in 24 countries could provide a meal for close to a billion people a day. New Englanders can also help ocean ecosystems recover by eating wild fish, choosing small fish, buying fish from the United States and eating mollusks, according to Andrew Sharpless, CEO of Oceana.

It's best to avoid eating shrimp because they are caught in nets that bring many species up accidentally, Sharpless said. The unwanted species are known as "by catch" and are tossed back into sea, usually dead. He also said carnivorous fish such as salmon should be caught in the wild rather than farmed.

ADVERTISEMENT

Since farming oysters, clams and mussels reduces pollution and builds local job opportunities, Sharpless said he recommends eating mollusks. "They're cleaning the ocean as they grow," he said. "We love the mollusk farmers."

As the world population approaches 9 billion, climate change advances and the middle class expands, Sharpless said livestock farming will put pressure on land ecosystems, forests and aquifers. The cost of grain also will increase, causing shortages for poor communities.

"We all don't want to have to choose between biodiversity and feeding people," said Sharpless, who recently coauthored a book titled "The Perfect Protein: The Fish Lover's Guide to Saving the Oceans and Feeding the World."